Comparison of the diagnostic and prognostic abilities of flexible laryngoscopy and dynamic digital radiography for vocal cord paralysis: A prospective observational study.

BACKGROUND: Although flexible laryngoscopy (FL) is the reference modality for diagnosing vocal cord paralysis (VCP), FL involves patient discomfort and insertion intolerance. Dynamic digital radiography (DDR) with high spatial and temporal resolution is easier to use and less invasive when evaluating VCP. METHODS: Seventy-eight patients underwent FL and DDR before and after neck surgery. Qualitative and quantitative vocal cord movement (VCM) evaluations were conducted. Patients with postoperative VCP were followed-up regularly. RESULTS: DDR exhibited diagnostic performance with 67% sensitivity and 100% specificity. The cutoff for VCM was 2.4 mm, with DDR exhibiting 100% sensitivity and 78% specificity. All cords with transient VCP had positive VCM at both 3 weeks and 2 months. Additionally, 50% and 75% of cords with permanent VCP had negative VCM at 3 weeks and 2 months, respectively. CONCLUSIONS: DDR is promising for the diagnosis of postoperative VCP and early prediction of permanent postoperative VCP.

Renal arteriovenous malformation treated using glue embolization under inflow and outflow control by balloon occlusion.

A 45-year-old female presented with gross hematuria. Right renal arteriovenous malformation on abdominal contrast-enhanced computed tomography necessitated urgent transcatheter arterial embolization. Right renal digital subtraction angiography revealed a single tortuous and dilated vessel converging to an aneurysmal dilated vein. To selectively embolize the malformation, we closed the arterial side with a microballoon and attempted glue embolization; filling occurred unexpectedly early, and another balloon on the vein side helped control the renal vein blood flow. Glue embolization was performed without adverse events. Glue embolization for high-flow arteriovenous malformation under balloon occlusion-mediated inflow and outflow control can effectively and safely embolize complete target vessels.

High-risk imaging characteristics in left ventricular apex for the life-threatening arrhythmic events in Japanese hypertrophic cardiomyopathy patients.

Left ventricular (LV) apical aneurysm is known to be associated with the life-threatening arrhythmic events in hypertrophic cardiomyopathy (HCM). However, the current 2014 ESC guideline has not included apical aneurysm as a major risk factor for sudden cardiac death and 2018 JCS guideline includes it only as a modulator, while it has been included as a new major risk marker in 2020 AHA/ACC guideline. Therefore, we sought to identify high-risk imaging characteristics in LV apex which is associated with a higher occurrence of ventricular tachycardia/fibrillation (VT/VF). In 99 consecutive Japanese HCM patients (median age, 65 years; 59 males) undergoing implantable cardioverter-defibrillator (ICD) implantation for primary prevention following cardiac magnetic resonance including late gadolinium enhancement (LGE), the occurrence of appropriate ICD interventions for VT/VF was evaluated for 6.2 (median) years after ICD implantation. Overall, appropriate ICD interventions occurred in 43% with annual rates of 7.0% for appropriate interventions. Kaplan-Meier analysis demonstrated that the presence of LV apical aneurysm was significantly associated with a higher occurrence of appropriate interventions (annual rates 18.9% vs. 6.4%, P = 0.013). Similarly, patients with high LV mid-to-apex pressure gradient (annual rates 14.9% vs. 6.2%, P = 0.022) and presence of apical LGE (annual rates 10.9% vs. 4.0%, P = 0.001) experienced appropriate interventions more frequently. An aneurysm, high-pressure gradient, and LGE in an apex are associated with VT/VF. These characteristics in apex should be kept in mind when implanting ICD in Japanese HCM patients as a primary prevention.

Image quality of coronary CT angiography at ultra low tube voltage reconstructed with a deep-learning image reconstruction algorithm in patients of different weight.

Background: GE Healthcare's new generation of deep-learning image reconstruction (DLIR), the Revolution Apex CT is the first CT image reconstruction engine based on a deep neural network to be approved by the US Food and Drug Administration (FDA). It can generate high-quality CT images that restore the true texture with a low radiation dose. The aim of the present study was to assess the image quality of coronary CT angiography (CCTA) at 70 kVp with the DLIR algorithm as compared to the adaptive statistical iterative reconstruction-Veo (ASiR-V) algorithm in patients of different weight. Methods: The study group comprised 96 patients who underwent CCTA examination at 70 kVp and were subdivided by body mass index (BMI) into normal-weight patients [48] and overweight patients [48]. ASiR-V40%, ASiR-V80%, DLIR-low, DLIR-medium, and DLIR-high images were obtained. The objective image quality, radiation dose, and subjective score of the two groups of images with different reconstruction algorithms were compared and statistically analyzed. Results: In the overweight group, the noise of the DLIR image was lower than that of the routinely used ASiR-40%, and the contrast-to-noise ratio (CNR) of DLIR (H: 19.15±4.31; M: 12.68±2.91; L: 10.59±2.32) was higher than that of the ASiR-40% reconstructed image (8.39±1.46), with statistically significant differences (all P values <0.05). The subjective image quality evaluation of DLIR was significantly higher than that of ASiR-V reconstructed images (all P values <0.05), with the DLIR-H being the best. In a comparison of the normal-weight and overweight groups, the objective score of the ASiR-V-reconstructed image increased with increasing strength, but the subjective image evaluation decreased, and both differences (i.e., objective and subjective) were statistically significant (P<0.05). In general, the objective score of the DLIR reconstruction image between the two groups increased with increased noise reduction, and the DLIR-L image was the best. The difference between the two groups was statistically significant (P<0.05), but there was no significant difference in subjective image evaluation between the two groups. The effective dose (ED) of the normal-weight group and the overweight group was 1.36±0.42 and 1.59±0.46 mSv, respectively, and was significantly higher in the overweight group (P<0.05). Conclusions: As the strength of the ASiR-V reconstruction algorithm increased, the objective image quality increased accordingly, but the high-strength ASiR-V changed the noise texture of the image, resulting in a decrease in the subjective score, which affected disease diagnosis. Compared with the ASiR-V reconstruction algorithm, the DLIR reconstruction algorithm improved the image quality and diagnostic reliability for CCTA in patients with different weights, especially in heavier patients.

Effect of an Ultrahigh b Value of 3000 s/mm2 and the Minimal Echo-time on Image Quality and the T2 Shine-through Effect in Diffusion-weighted Imaging of the Liver at 3T: Phantom and Clinical Pilot Studies.

PURPOSE: To assess the effect of an ultrahigh b value of 3000 s/mm2 and the minimal TE of 53 ms on image quality and T2 shine-through effect in liver diffusion-weighted imaging (DWI) using a 3-Tesla MRI scanner with a peak gradient of 100 mT/m. METHODS: At b values of 1000 and 3000 s/mm2 and at the minimal (44-53 ms) and routine TEs (70 ms), DWI of our original phantom and liver DWI in 10 healthy volunteers and 26 patients with 35 hepatic hemangiomas were acquired with this scanner, and the quantified SNR of the phantom and the hepatic parenchyma in the volunteers and the contrast-to-noise ratio (CNR) of the hepatic hemangiomas were calculated; two independent readers qualitatively graded the overall image quality in the volunteers and determined the presence or absence of the T2 shine-through effect related to the hemangiomas in the patients. We compared the SNR and subjective overall image quality between the minimal and routine TEs and the CNR and incidence of the T2 shine-through effect between b values of 1000 and 3000 s/mm2. Inter-reader agreement was also evaluated. RESULTS: The SNR at both b values was significantly higher, and the subjective overall image quality at a b value of 3000 s/mm2 was significantly better at the minimal TE than at the routine TE (P < 0.05 for all). The CNR at both TEs and the incidence of the T2 shine-through effect at the minimal TE were significantly lower at a b value of 3000 s/mm2 than at a b value of 1000 s/mm2 (P < 0.05 for all). Inter-reader agreement was excellent. CONCLUSION: Liver DWI at the ultrahigh b value can reduce the T2 shine-through effect with improvement of image quality using the minimal TE.

Deep learning-based age estimation from chest X-rays indicates cardiovascular prognosis.

BACKGROUND: In recent years, there has been considerable research on the use of artificial intelligence to estimate age and disease status from medical images. However, age estimation from chest X-ray (CXR) images has not been well studied and the clinical significance of estimated age has not been fully determined. METHODS: To address this, we trained a deep neural network (DNN) model using more than 100,000 CXRs to estimate the patients' age solely from CXRs. We applied our DNN to CXRs of 1562 consecutive hospitalized heart failure patients, and 3586 patients admitted to the intensive care unit with cardiovascular disease. RESULTS: The DNN's estimated age (X-ray age) showed a strong significant correlation with chronological age on the hold-out test data and independent test data. Elevated X-ray age is associated with worse clinical outcomes (heart failure readmission and all-cause death) for heart failure. Additionally, elevated X-ray age was associated with a worse prognosis in 3586 patients admitted to the intensive care unit with cardiovascular disease. CONCLUSIONS: Our results suggest that X-ray age can serve as a useful indicator of cardiovascular abnormalities, which will help clinicians to predict, prevent and manage cardiovascular diseases.

Chest X-ray is one of the most widely used medical imaging tests worldwide to diagnose and manage heart and lung diseases. In this study, we developed a computer-based tool to predict patients' age from chest X-rays. The tool precisely estimated patients' age from chest X-rays. Furthermore, in patients with heart failure and those admitted to the intensive care unit for cardiovascular disease, elevated X-ray age estimated by our tool was associated with poor clinical outcomes, including readmission for heart failure or death from any cause. With further testing, our tool may help clinicians to predict outcomes in patients with heart disease based on a simple chest X-ray.

Correlation between CT Value on Lung Subtraction CT and Radioactive Count on Perfusion Lung Single Photon Emission CT in Chronic Thromboembolic Pulmonary Hypertension.

Background: Lung subtraction CT (LSCT), the subtraction of noncontrast CT from CT pulmonary angiography (CTPA) without spatial misregistration, is easily applicable by utilizing a software-based deformable image registration technique without additional hardware and permits the evaluation of lung perfusion as iodine accumulation, similar to that observed in perfusion lung single photon emission CT (PL-SPECT). The aim of this study was to use LSCT to newly assess the quantitative correlation between the CT value on LSCT and radioactive count on PL-SPECT as a reference and validate the quantification of lung perfusion by measuring the CT value in chronic thromboembolic pulmonary hypertension (CTEPH). Methods: We prospectively enrolled 47 consecutive patients with CTEPH undergoing both LSCT and PL-SPECT; we used noncontrast CT, CTPA, and LSCT to measure CT values and PL-SPECT to measure radioactive counts in areas representing three different perfusion classes­no perfusion defect, subsegmental perfusion defect, and segmental perfusion defect; we compared CT values on noncontrast CT, CTPA, and LSCT and radioactive counts on PL-SPECT among the three classes, then assessed the correlation between them. Results: Both the CT values and radioactive counts differed significantly among the three classes (p < 0.01 for all) and showed weak correlation (ρ = 0.38) by noncontrast CT, moderate correlation (ρ = 0.61) by CTPA, and strong correlation (ρ = 0.76) by LSCT. Conclusions: The CT value measurement on LSCT is a novel quantitative approach to assess lung perfusion in CTEPH and only correlates strongly with radioactive count measurement on PL-SPECT.

Denoising using deep-learning-based reconstruction for whole-heart coronary MRA with sub-millimeter isotropic resolution at 3 T: a volunteer study.

PURPOSE The aim of this study was to assess the usefulness of denoising deep-learning-based reconstruction (dDLR) to improve image quality and vessel delineation in noncontrast 3-T wholeheart coronary magnetic resonance angiography (WHCMRA) with sub-millimeter isotropic resolution (Sub-mm) compared with a standard resolution without dDLR (Standard). METHODS For 10 healthy volunteers, we acquired the WHCMRA with Sub-mm with and without dDLR and Standard to quantify signal- (SNR) and contrast-to-noise ratio (CNR) and vessel edge signal response (VESR) in all the 3 image types. Two independent readers subjectively graded vessel sharpness and signal homogeneity of 8 coronary segments in each patient. We used Kruskal- Wallis test with Bonferroni correction to compare SNR, CNR, VESR, and the subjective evaluation scores among the 3 image types and weighted kappa test to evaluate inter-reader agreement on the scores. RESULTS SNR was significantly higher with Sub-mm with dDLR (P < .001) and Standard (P=.005) than with Sub-mm without dDLR and was comparable between Sub-mm with dDLR and Standard (P=.511). CNR was significantly higher with Sub-mm with dDLR (P < .001) and Standard (P=.005) than with Sub-mm without dDLR and was comparable between Sub-mm with dDLR and Standard (P=.560). VESR was significantly greater with Sub-mm with (P=.001) and without dDLR (P=.017) than with Standard and was comparable between Sub-mm with and without dDLR (P=1.000). In the proximal, middle, distal, and all the coronary segments, the subjective vessel sharpness was significantly better with Sub-mm with dDLR than Sub-mm without dDLR and Standard (P < .001, for all) and was comparable between Sub-mm without dDLR and Standard (P > .05); the subjective signal homogeneity was significantly improved from Sub-mm without dDLR to Standard to Sub-mm with dDLR (P < .001). The inter-reader agreement was excellent (kappa=0.84). CONCLUSION Application of dDLR is useful for improving image quality and vessel delineation in the WHCMRA with Sub-mm compared with Standard.

Bilateral recurrent laryngeal nerve paralysis diagnosed using dynamic digital radiography during the COVID-19 pandemic.

Dynamic digital radiography (DDR) is a motion-detecting technique with high temporal resolution. Flexible laryngoscopy is a common modality for the observation of the larynx; however, it generates aerosol. DDR is an easy and less risky screening test for the diagnosis of recurrent laryngeal nerve paralysis during the COVID-19 pandemic.

Clinical validity of non-contrast-enhanced VI-RADS: prospective study using 3-T MRI with high-gradient magnetic field.

OBJECTIVES: To develop a modified Vesical Imaging Reporting and Data System (VI-RADS) without dynamic contrast-enhanced imaging (DCEI), termed "non-contrast-enhanced VI-RADS (NCE-VI-RADS)", and to assess the additive impact of denoising deep learning reconstruction (dDLR) on NCE-VI-RADS. METHODS: From January 2019 through December 2020, 163 participants who underwent high-gradient 3-T MRI of the bladder were prospectively enrolled. In total, 108 participants with pathologically confirmed bladder cancer by transurethral resection were analyzed. Tumors were evaluated based on VI-RADS (scores 1-5) by two readers independently: an experienced radiologist (reader 1) and a senior radiology resident (reader 2). Conventional VI-RADS assessment included all three imaging types (T2-weighted imaging [T2WI], diffusion-weighted imaging [DWI], and dynamic contrast-enhanced imaging [DCEI]). Also evaluated were NCE-VI-RADS comprising only non-contrast-enhanced imaging types (T2WI and DWI), and "NCE-VI-RADS with dDLR" comprising T2WI processed with dDLR and DWI. All systems were assessed using receiver-operating characteristic curve analysis and simple and/or weighted κ statistics. RESULTS: Muscle invasion was identified in 23/108 participants (21%). Area under the curve (AUC) values for diagnosing muscle invasion were as follows: conventional VI-RADS, 0.94 and 0.91; NCE-VI-RADS, 0.93 and 0.91; and "NCE-VI-RADS with dDLR", 0.96 and 0.93, for readers 1 and 2, respectively. Simple κ statistics indicated substantial agreement for NCE-VI-RADS and almost perfect agreement for conventional VI-RADS and "NCE-VI-RADS with dDLR" between the two readers. CONCLUSION: NCE-VI-RADS achieved predictive accuracy for muscle invasion comparable to that of conventional VI-RADS. Additional use of dDLR improved the diagnostic accuracy of NCE-VI-RADS. KEY POINTS: • Non-contrast-enhanced Vesical Imaging Reporting and Data System (NCE-VI-RADS) was developed to avoid risk related to gadolinium-based contrast agent administration. • NCE-VI-RADS had predictive accuracy for muscle invasion comparable to that of conventional VI-RADS. • The additional use of denoising deep learning reconstruction (dDLR) might further improve the diagnostic accuracy of NCE-VI-RADS.

Proposal for a New Vesical Imaging-Reporting and Data System (VI-RADS)-Based Algorithm for the Management of Bladder Cancer: A Paradigm Shift From the Current Transurethral Resection of Bladder Tumor (TURBT)-Dependent Practice.

Transurethral resection of bladder tumor (TURBT) is the essential first step in the current algorithm for the management of bladder cancer (BC). However, despite its necessity and significance, TURBT has several limitations, including cost, hospitalization, anesthesia, potential complications such as bladder perforation, and delay to radical cystectomy. The Vesical Imaging Reporting and Data System (VI-RADS) was developed to standardize the reporting of multiparametric magnetic resonance imaging for BC, and its diagnostic accuracy to predict muscle invasion has been validated. Given the high sensitivity of VI-RADS ≥ 3 and high specificity of VI-RADS ≥ 4 as clinically relevant cutoff values, we herein propose a new VI-RADS-based algorithm for the management of BC. Using this algorithm, patients with VI-RADS ≤ 2 may not need to undergo sampling of the detrusor muscle nor second TURBT even if there is no muscle in the initial TURBT specimen, whereas patients with VI-RADS ≥ 4 may skip conventional TURBT aimed at pathologic confirmation of muscle invasion and immediately undergo radical cystectomy. Our newly proposed algorithm enables the avoidance of unnecessary deep resection or second TURBT as well as delay to radical cystectomy. The VI-RADS-based algorithm enables a paradigm shift from the current TURBT-dependent practice in the management of BC.

Image quality and radiologists' subjective acceptance using model-based iterative and deep learning reconstructions as adjuncts to ultrahigh-resolution CT in low-dose contrast-enhanced abdominopelvic CT: phantom and clinical pilot studies.

PURPOSE: In contrast-enhanced abdominopelvic CT (CE-APCT) for oncologic follow-up, ultrahigh-resolution CT (UHRCT) may improve depiction of fine lesions and low-dose scans are desirable for minimizing the potential adverse effects by ionizing radiation. We compared image quality and radiologists' acceptance of model-based iterative (MBIR) and deep learning (DLR) reconstructions of low-dose CE-APCT by UHRCT. METHODS: Using our high-resolution (matrix size: 1024) and low-dose (tube voltage 100 kV; noise index: 20-40 HU) protocol, we scanned phantoms to compare the modulation transfer function and noise power spectrum between MBIR and DLR and assessed findings in 36 consecutive patients who underwent CE-APCT (noise index: 35 HU; mean CTDIvol: 4.2 ± 1.6 mGy) by UHRCT. We used paired t-test to compare objective noise and contrast-to-noise ratio (CNR) and Wilcoxon signed-rank test to compare radiologists' subjective acceptance regarding noise, image texture and appearance, and diagnostic confidence between MBIR and DLR using our routine protocol (matrix size: 512; tube voltage: 120 kV; noise index: 15 HU) for reference. RESULTS: Phantom studies demonstrated higher spatial resolution and lower low-frequency noise by DLR than MBIR at equal doses. Clinical studies indicated significantly worse objective noise, CNR, and subjective noise by DLR than MBIR, but other subjective characteristics were better (P < 0.001 for all). Compared with the routine protocol, subjective noise was similar or better by DLR, and other subjective characteristics were similar or worse by MBIR. CONCLUSION: Image quality, except regarding noise characteristics, and acceptance by radiologists were better by DLR than MBIR in low-dose CE-APCT by UHRCT.

Pulmonary Artery Aneurysm Diagnosed by Dynamic Digital Chest Radiography.

Pulmonary artery aneurysms (PAAs) are rare but clinically important because their rupture can cause sudden death. This report describes a case of an asymptomatic patient with an unruptured PAA that was successfully diagnosed by dynamic digital chest radiography (DDCR) and was treated surgically. DDCR is an advanced, temporally resolved radiographic technique that offers high-quality fluoroscopy-like images at a low radiation dose. Although noncontrast chest computed tomography revealed only a nonspecific nodule, DDCR delineated this lesion as a pulsatile nodule synchronized with cardiac pulsations, thereby establishing the diagnosis of PAA. This diagnosis was confirmed by computed tomographic pulmonary angiography and surgery.

Novel diagnostic and therapeutic approaches to pulmonary hypertension due to the unilateral absence of a pulmonary artery.

We report the case of a 64-year-old female diagnosed with severe pulmonary hypertension due to the unilateral absence of a pulmonary artery. The four-dimensional computed tomography scan is a useful modality for revealing detailed anatomical findings for differential diagnoses and surgical decision-making. The patient had severe pulmonary hypertension with a mean pulmonary artery pressure (PAP) of 74 mmHg and was treated with triple upfront combination therapy, leading to significant improvement in pulmonary haemodynamics (to 27 mmHg in mean PAP) and functional capacity (WHO functional class, from III to II; 6-min walk distance, from 211 to 276 m).

Emergent transcatheter arterial embolization to control critical blood pressure fluctuation associated with hypercatecholaminemic crisis in a patient with an unruptured retroperitoneal paraganglioma.

Pheochromocytoma/paraganglioma (PPGL)-related hypercatecholaminemic crisis is a rare lethal condition caused by uncontrolled catecholamine secretion, occasionally leading to critical fluctuation in blood pressure (BP). Emergent transcatheter arterial embolization (TAE) has been employed for spontaneous PPGL rupture, but never, to our knowledge, for critical fluctuation in BP associated with PPGL-related hypercatecholaminemic crisis. We describe here our experience utilizing this method to control critical fluctuation in BP associated with this crisis in a 44-year-old man with an unruptured retroperitoneal paraganglioma. The patient experienced sudden severe left abdominal pain and came to our emergency department, where he exhibited severe fluctuation in BP and underwent laboratory testing that showed hypercatecholaminuria and computed tomography (CT) that revealed a left retroperitoneal tumor with no apparent intra- or retroperitoneal hematoma. We performed emergent TAE from the left inferior phrenic artery using gelatin sponge, which stabilized his BP and relieved his abdominal pain. Histologic examination following elective surgical resection of the tumor confirmed our diagnosis of unruptured retroperitoneal paraganglioma. We believe that TAE represents an important option for the emergent treatment of the critical BP fluctuation associated with PPGL-related hypercatecholaminemic crisis.

Prospective Validation of Vesical Imaging-Reporting and Data System Using a Next-Generation Magnetic Resonance Imaging Scanner-Is Denoising Deep Learning Reconstruction Useful?

PURPOSE: The Vesical Imaging Reporting and Data System (VI-RADS) was launched in 2018 to standardize reporting of magnetic resonance imaging for bladder cancer. This study aimed to prospectively validate VI-RADS using a next-generation magnetic resonance imaging scanner and to investigate the usefulness of denoising deep learning reconstruction. MATERIALS AND METHODS: We prospectively enrolled 98 patients who underwent bladder multiparametric magnetic resonance imaging using a next-generation magnetic resonance imaging scanner before transurethral resection of bladder tumor. Tumors were categorized according to VI-RADS, and we ultimately analyzed 68 patients with pathologically confirmed urothelial bladder cancer. We used receiving operating characteristic curve analyses to assess the predictive accuracy of VI-RADS for muscle invasion. Sensitivity, specificity, positive/negative predictive value, accuracy and area under the curve were calculated for different VI-RADS score cutoffs. RESULTS: Muscle invasion was detected in the transurethral resection of bladder tumor specimens of 18 patients (26%). The optimal cutoff value of the VI-RADS score was determined as ≥4 based on the receiver operating curve analyses. The accuracy of diagnosing muscle invasion using a cutoff of VI-RADS ≥4 was 94% (AUC 0.92). Additionally, we assessed the utility of denoising deep learning reconstruction. Combination with denoising deep learning reconstruction significantly improved the AUC of category by T2-weighted imaging, and of the 4 patients who were misdiagnosed by the final VI-RADS score 3 were correctly diagnosed by T2-weighted imaging+denoising deep learning reconstruction. CONCLUSIONS: In this prospective validation study with a next-generation magnetic resonance imaging scanner, VI-RADS showed high predictive accuracy for muscle invasion in patients with bladder cancer before transurethral resection of bladder tumor. Combining T2-weighted imaging with denoising deep learning reconstruction might further improve the diagnostic accuracy of VI-RADS.